9,088 research outputs found
Interchange reconnection associated with a confined filament eruption: Implications for the source of transient cold-dense plasma in solar winds
The cold-dense plasma is occasionally detected in the solar wind with in situ
data, but the source of the cold-dense plasma remains illusive. Interchange
reconnections (IRs) between closed fields and nearby open fields are well known
to contribute to the formation of solar winds. We present a confined filament
eruption associated with a puff-like coronal mass ejection (CME) on 2014
December 24. The filament underwent successive activations and finally erupted,
due to continuous magnetic flux cancellations and emergences. The confined
erupting filament showed a clear untwist motion, and most of the filament
material fell back. During the eruption, some tiny blobs escaped from the
confined filament body, along newly-formed open field lines rooted around the
south end of the filament, and some bright plasma flowed from the north end of
the filament to remote sites at nearby open fields. The newly-formed open field
lines shifted southward with multiple branches. The puff-like CME also showed
multiple bright fronts and a clear southward shift. All the results indicate an
intermittent IR existed between closed fields of the confined erupting filament
and nearby open fields, which released a portion of filament material (blobs)
to form the puff-like CME. We suggest that the IR provides a possible source of
cold-dense plasma in the solar wind
Enhanced collectivity in neutron-deficient Sn isotopes in energy functional based collective Hamiltonian
The low-lying collective states in Sn isotopes are studied by a
five-dimensional collective Hamiltonian with parameters determined from the
triaxial relativistic mean-field calculations using the PC-PK1 energy density
functional. The systematics for both the excitation energies of states
and values are reproduced rather well, in particular,
the enhanced E2 transitions in the neutron-deficient Sn isotopes with N<66. We
show that the gradual degeneracy of neutron levels 1g7/2 and 2d5/2 around the
Fermi surface leads to the increase of level density and consequently the
enhanced paring correlations from N=66 to 58. It provokes a large quadrupole
shape fluctuation around the spherical shape, and leads to an enhanced
collectivity in the isotopes around N=58.Comment: 5 pages, 4 figures, accepted for publication in Physics Letters
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